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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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This cohesive, connected, and constant collaboration and dynamic approach to inputs and feedback to achieve a workable solution represents the agility necessary for responsive manufacturing.
As part of a Battery 500 seedling project, MBRDNA partnered with LBNL and Montana State University (MSU) to develop solid-state batteries based on an Al-substituted LLZO (Li 7 La 3 Zr 2 O 12 ) ceramic ion-conductor. All solid-state lithium batteries are attractive contenders for use as power sources for electric vehicles because of their potential for better safety and higher energy density than state-of-the-art lithium-ion batteries, although they are still at early stages of development. Al-substituted LLZO is one of the most promising solid electrolytes for battery applications based on high ionic conductivity, a wide operating voltage window, and apparent stability vs. reduction by lithium. However, difficulties with processing thin (< 20 $\textit{um}$ and dense LLZO membranes have hampered development of devices based on this material. It is non-compressible and must be sintered at high temperatures to densify components. It is also difficult to maintain contact between the active cathode material and LLZO in the composite cathodes, which is critical for successful operation. This research project aimed to use novel processing methods to overcome these issues. The end result was the first ever-reported truly all solid-state battery based on LLZO operating at room temperature without application of exogenous pressure. During the course of the project, we also identified a number of issues that need to be addressed to improve the technology readiness level of this battery.
The main goal of this project was to increase the beneficial use of fly ash as a supplementary cementitious material for precast concrete applications. A major focus was to develop balanced concrete mix design strategies which collectively satisfy the follow objectives: 1) increase fly ash beneficial use by at least 15% in the precast concrete industry, 2) maintain or exceed stringent structural property requirements (e.g., compressive strength at initial prestress, modulus of rupture, etc.), 3) exhibit little or no additional cost relative to conventional mixtures, and 4) mitigate detrimental environmental consequences inadvertently caused by increased beneficial use. Outcomes from this project include recommendations for design guidelines and code provisions for sustainable concrete mix designs, facilitating diversion and harvesting of large quantities of fly ash from landfills or impoundments, and multiple frameworks for incorporating discarded fly ash materials (i.e., landfilled or ponded fly ash after separating the impurities) in concrete construction.
Network Time Protocol (NTP), as it traditionally generated and widely consumed, is a legacy system with known security vulnerabilities. The vulnerabilities can be mitigated by modern implementations of NTP that use internal and external redundancy for better accuracy and fault tolerance. Precision Time Protocol (PTP) is an alternative that uses master clocks inside secure networks to eliminate the known vulnerabilities of NTP.
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Two-way satellite time and frequency transfer (TWSTFT) has been a trusted time transfer and synchronization method for a long time. It provides good timing accuracy, usually 100 ns or less. The setup of two-way satellite time and frequency transfer (TWSTFT) coordination and communication are crucial to having a system that runs and works as it should, especially when the setup involves traveling and working at a third-party facility. Even with perfect planning, some problems will arise; this document describes TWSTFT setup and lessons learned.
Stable and accurate timing forms the foundation of many modern essential services. While Global Navigation Satellite Systems (GNSS) provide a cheap way to achieve extremely accurate timing, these systems are vulnerable to interference and complete outages, forcing systems that rely on them into a state of holdover. Testing and characterizing holdover performance is therefore essential for ensuring that these modern services do not go down when GNSS-based timing is unavailable.
Stable and accurate timing forms the foundation of many modern essential services. While Global Navigation Satellite Systems (GNSS) provide a cheap way to achieve extremely accurate timing, these systems are vulnerable to interference and complete outages, forcing systems that rely on them into a state of holdover. Testing and characterizing holdover performance is therefore essential for ensuring that these modern services do not go down when GNSS-based timing is unavailable.
The overall objective of this project was to produce a coal-based construction material that has up to ~95 weight percent (wt. %) coal with physical, chemical, and thermal properties exceeding those of ordinary Portland cement (OPC)-based construction materials. Additionally, the project aimed to minimize external binders by implementing novel mixing techniques, while exceeding the performance/cost ratio of OPC. Finally, the project was to demonstrate production of precast products via the design and fabrication of products via a bench scale process. Consistent with some of these objectives, the project successfully fabricated samples of coal-based composite materials with >80 wt% coal with physical, chemical and thermal properties on par with cement-based concrete. Select samples demonstrated compressive strengths with >7,000 psi and flexural strength of >420 psi. The composite materials minimized external binders and also demonstrated durability, as evidenced by resistance to acidic and basic solutions. Finally, larger slab and beam type samples were produced using a process developed by the Recipient, although, the process was not semicontinuous in nature. Taken together, the results of this project suggest that domestic coal has potential to serve as a replacement for cementitious materials utilized in incumbent construction technologies, which could significantly reduce the energy and emissions of the construction industry
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Vacuum forming of a sheet of thermoplastic material around a mandrel conforming to the shape of the finished object provides a pattern for an investment mold. The thickness of the metal part is determined by the thickness of the plastic pattern.
Whisker reinforcement of cobalt-base alloys
Evaluation of the stress-corrosion characteristics of aluminum alloy M-45 shows that the most favorable artificial aging cycle for this alloy, with regard to optimum strength and stress-corrosion resistance, appears to be 400 degrees F for 12 hours.
Repair operation for damaged aluminum parts includes anodizing the part, removing the oxide layer, filling the pit or scratch with copper, capping the fill with cadmium, and hand polishing.
Cryogenic fatigue and tensile properties for metallic materials are determined in the operating life-time range of ten thousand to ten million cycles at room temperature, at minus 320 degrees F, and at minus 423 degrees F. Results are presented as stress versus number of cycles to failure.
Method for making screen with unlimited fineness of mesh and screen thickness